Don't buy that plant!

As a garden writer, I'm usually in the position of encouraging people to buy plants. I have no financial interest in doing so, of course, but I want others to also enjoy the flowers, vegetables, shrubs, trees, and more that I like and have had success with.

But this time of year, the situation is reversed. Although I continue to talk about my favorites, I often find myself saying, "But don't buy it yet."

" Why not?" is usually the answer. "After all, I was just in [insert name of big-box or chain store here] and they had all kinds of plants. They looked good."

I only hope the person I'm talking to doesn't add that they bought some annual vinca and tomato plants. If they have, I groan.

I'm not the only one to react like that. Kim Pokorny of The Oregonian feel the same way.

The reason for all this unhappiness is that in many places, the plants go out on display in stores long before the weather and soil have warmed enough for planting. Unsuspecting homeowners buy them, put them in the ground, and then discover that either (1) the young plants are killed by frost or (2) they don't grow well.

The reason is that tomatoes want -- and need -- warm weather! The same is true of marigolds (natives of Mexico) and many of our other favorite plants of summer.

Moral of the story: Know when the average last frost date is in your area. Your local Extension Service office can tell you. So can any experienced gardener in your neighborhood.

There's one caveat to that advice: Note the word "average." There's no guarantee that frost will magically disappear because April 15 comes and goes. So watch the local weather forecast each evening, to be sure that a cold front isn't imminent.

Actually, although spring fever often tricks us into rushing, there's little advantage to being the early bird planter of warm-season plants. Those set out two or three weeks later than the last-frost date usually catch up and do just as well, if not better, than the early ones.

So, if there still might be a cold snap in your future and you've just got to plant now, choose plants that can take some cold -- English peas, broccoli, cabbage, Brussels sprouts, celery, kale, turnips, carrots, beets, spinach, and cauliflower.

Primroses and pansies are fine, too. But success with other plants will come with patience and resisting the temptation to plant too early.

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